1. Preheat your oven to 425°F.
2. Make a crosscut across the round side of each chestnut to keep them from exploding, and arrange them along with the unpeeled garlic cloves on a cookie sheet.
3. Roast until the skins have pulled back from the cuts and the nutmeats have softened (exactly how long will depend upon the chestnuts, about 20 minutes for small, 25 minutes for large.).
4. Remove the nuts from the oven, make a mound of them in an old towel, wrap them up, and squeeze them hard to release the skin. Allow to cool until you can peel them.
5. Peel the garlic cloves out of the skins, and sauté with the onions over medium-high heat until lightly caramelized.
6. Sprinkle with nutmeg and allspice and cook for 1 minute.
7. Crumble chestnuts into the pan mixture. Add the olive oil, vinegar and water and cook for 4 minutes or until the chestnuts are moist.
8. Allow to cool, then pour ingredients into a food processor and process until smooth.
Makes 6-8 servings.
